A recently published study finds that the island Pacific has lost over 1,000 species of bird since the arrival of the first human colonists.
The former existence of now extinct birds in the Pacific islands is discovered through archaeological digs which are slowly building up the fossil record, but most extinct species remain undiscovered because fossil hunting across the islands is very patchy and incomplete.
But scientists have long known that human colonization of oceanic Pacific islands over the past 3,500 islands resulted in the extinction of large flightless birds but have little more than guesstimated at the numbers involved.
Using statistical analysis researcher Richard Duncan (Univ. of Canberra) and his colleagues have concluded that human settlement of the Pacific islands resulted in the loss of about 1,000 species of nonpasserine landbirds (birds other than seabirds and songbirds which, if included, would have increased the number).
This is about 10% of the current global total of about 10,000 birds of all sorts.
Many of the extinct species had become flightless on their island homes because of the absence of predators. Not only were they a convenient human food source, but they were vulnerable to introduced predators brought by the first colonists including rats, dogs and pigs, as well as the colonist’s activities such as fire-induced habitat modification.
The fossil record in Fiji remains poorly known but we do know that there was a distinctive megafauna in the islands which included a crocodile, a tortoise, a giant ground frog, a giant iguana and two giant birds.
One of the most remarkable of the birds was a large flightless pigeon about the size of the well known Dodo of Mauritius, Natunaornis gigoura, which is known as a fossil from the Volivoli cave system, Sigatoka. In all seven globally extinct birds are currently known from the fossil evidence.
This included two or more megapodes (one of them a ‘giant’), megapodes are birds which do not incubate their eggs but use the warmth of decomposing vegetation or thermal ducts.
There were also several rails, one of which the barred-winged rail Hypotaenidia poeciloptera survived through to the late 19th century, succumbing after the arrival of Europeans.